Now the Trojan horse arrives by telephone: Hackers have another weapon at their disposal, the computer bulletin board. Mike Holderness explains

The silent world of computer communications is facing a noisy split. Computer 'bulletin boards' - services that enable users to communicate over telephone lines by leaving messages, sharing files and holding discussions - have become the subject of growing concern.

Today, representatives of computer software producers will meet Emma Nicholson, Conservative MP for Devon West and Torridge and a former computer consultant, to urge regulation of bulletin boards.

Roger Bennett, of the European Leisure Software Producers' Association, says there is evidence that bulletin boards are being used for hacking and pirating of software.

Moral questions also have been raised. Bob Hay, of the Federation Against Software Theft, says: 'I think everyone would have a concern about hardcore porn being on bulletin boards. A lot of personal computers are used by young people.

'We've also found recipes to make LSD, high explosives using fertiliser, a device to by-pass telecommunications charges and instructions for making an electricity meter go in reverse.'

Users of bulletin boards, meanwhile, are concerned that any attempt to regulate their global electronic networks could lead to restrictions on the free flow of information.

Last Thursday, a group of users announced a campaign against the threatened regulation. Earlier this month, another group, called CommUnity, launched itself with a series of electronic messages.

Opponents of regulation say that the information which worries Mr Hay is available on paper to any clever science student with access to a library. Driving much of the concern over bulletin boards, however, is the spectre of the wily hacker - a teenager in an untidy, suburban bedroom - breaking into the Pentagon's computer systems and causing a world war.

Electronic mischief and break- ins certainly occur. Two weeks ago, a systems operator of a large computer enthusiasts' bulletin board in London received an irate message from an Italian university. 'Your computer has been used by a hacker to place a Trojan horse,' the message said. 'Please check who was connected at the following times. . . . ' A Trojan horse is a computer program that disguises its true purpose.

'I spent all Saturday night correlating the times spent on the Italian system and the time the user spent on here,' the operator says. He tracked down the subscriber causing the problem and cancelled their account, which had been opened with a false credit card. The user had been connecting to the London system from the West Coast of the United States, and then going out again to Italy.

London University's Imperial College has also suffered at the hands of hackers. Lee McLoughlin, a computer systems administrator, says: 'The people causing me grief were operating out of an academic institutionin the Southampton area. In December, there were 40 or 50 at a time swamping our machines, so we banned everyone from that site. Now they have stopped using the academic computer and have switched to an underground bulletin board.'

Victims of electronic abuse usually have no idea of the hackers' identities. However, some groups have become known. The Legion of Doom was the name used by a group of self- proclaimed hackers based in the United States.

Bruce Sterling, author of the recently published The Hacker Crackdown (Viking, pounds 16.99), says: 'There was a fairly well-known Legion of Doom member who used to live in England. There is also a group called Cartel, which seems to have English and German members.'

About three-quarters of the intrusion cases reported to the Metropolitan Police computer crime unit appear to involve simple inquisitiveness. 'In a lot of the others, there's a commercial aspect involved, and companies often don't report it,' says a member of the unit, who declined to be identified. 'We have to gain the commercial sector's confidence that we will respect the confidentiality of their data.'

Hackers use modems to translate computer codes into a series of squawks that can be sent over a phone line. They subscribe to bulletin boards which enable them to send computer text, programs, encoded pictures and other computer files to other users. Many part-time programmers 'up- load' their efforts to bulletin boards, so that others can try them out. One group announced: 'Don't want money. Got money. Want admiration.'

Beyond the bulletin boards lies Internet, a worldwide network that links academic institutions and a growing number of companies and bulletin boards. It has between 8 million and 16 million subscribers and is free to academic users. It offers unparalleled facilities: with the appropriate passwords, a user could run a program on a supercomputer in New Mexico from a second-hand micro in a cramped attic in a London suburb.

To the students and scientists it is intended for, Internet is a powerful research tool, allowing the instant exchange of scientific papers and preliminary results as well as a particularly inane line in global gossip. To the hacker, it is a highway to perhaps 100,000 powerful computers. Mr McLoughlin says: 'It's fun to log into Hawaii and places like Nasa. Before the network became more secure, I was shown as an undergraduate how to log into the Strategic Air Command computer. (The computer, in Colorado, controls the US nuclear forces.) It was like climbing a mountain . . . because it's there.'

Mr Sterling says that apart from corporate crime, software piracy - the distribution of stolen copies of programs - is the major problem associated with bulletin boards. 'There are people who are convinced that if you're a hip dude with a modem, you ought to be able to get any software you want,' he says.

Nigel Hardy, one of the founders of CommUnity, acknowledges the existence of bulletin boards for pirating software. 'They are a tiny minority - maybe a dozen of the more than 400 bulletin boards operating in the UK,' he says.

Despite the concerns, however, a crackdown on bulletin boards appears unlikely. Law enforcement officers are doubtful about the benefits of regulation. As Emma Nicholson says: 'There are far too many regulations surrounding our daily lives, and

it seems to me that this rather clubbable activity doesn't need registration.

'It's a cheerful and constructive hobby. People have suddenly discovered bulletin boards and want to jump on them - most unfair in my opinion.'

(Photograph omitted)